<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title></title>
    <style>

        #center{
            margin-top: 150px;
            margin-left: auto;
            margin-right: auto;
            width:400px;
            height: 260px;
        }

        #header{
            float: left;
            width:390px;
            margin-left: auto;
            margin-right: auto;
            border-width: 1px;
            border-style: ridge;
            height: 30px;
            padding-top: 10px;
            padding-left: 10px;
            padding-bottom: 0px;
            background-color:rgb(130,154,168);
            color: white;
            font-weight:700;
        }

        #auth-form{
            float: left;
            position: relative;
            margin-left: auto;
            margin-right: auto;
            padding-top: 0px;
            margin-top: 0px;
            width:400px;
            border-width: 1px;
            border-style: ridge;
            height: 230px;
        }

    </style>
</head>
<body>
<pre>
    <div id="center">
    <div id="header">后台登陆</div>
    <div id="auth-form">
        <form autocomplete="off">
        <label>用户名:</label>
        <input type="text" name="username" style="height:23px;width:250px;">
        <label></label>
        <label>密码:</label>
        <input type="password" name="pwd" style="height:23px;width:250px;">
            <label></label>
        <input type="submit" value="登陆">
    </form>
    </div>
    </div>
</pre>
</body>
</html>